BUG: rwlock bad magic in ipv6_chk_mcast_addr

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3f8a27f9e27b Linux 4.19.211
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13ba1dcfb00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b9277b418617afe
dashboard link: https://syzkaller.appspot.com/bug?extid=6faadb40dfa15928cac8
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6faadb...@syzkaller.appspotmail.com

usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #1
usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #1
usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #1
usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #1
usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #1
BUG: rwlock bad magic on CPU#0, ksoftirqd/0/9, 0000000000f76a49
CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #1
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
rwlock_bug kernel/locking/spinlock_debug.c:140 [inline]
do_raw_read_lock+0x66/0x80 kernel/locking/spinlock_debug.c:153
ipv6_chk_mcast_addr+0x17a/0x6c0 net/ipv6/mcast.c:1005
usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #1
ip6_mc_input+0x2b8/0xa80 net/ipv6/ip6_input.c:444
dst_input include/net/dst.h:461 [inline]
ip6_rcv_finish+0x1d9/0x2f0 net/ipv6/ip6_input.c:76
NF_HOOK include/linux/netfilter.h:289 [inline]
ipv6_rcv+0xf2/0x3f0 net/ipv6/ip6_input.c:273
usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #1
usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #1
__netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:4954
usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #1
usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #1
__netif_receive_skb+0x27/0x1c0 net/core/dev.c:5066
process_backlog+0x241/0x700 net/core/dev.c:5849
napi_poll net/core/dev.c:6280 [inline]
net_rx_action+0x4ac/0xfb0 net/core/dev.c:6346
usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #1
__do_softirq+0x265/0x980 kernel/softirq.c:292
run_ksoftirqd+0x57/0x110 kernel/softirq.c:653
usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #1
smpboot_thread_fn+0x655/0x9e0 kernel/smpboot.c:164
usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #1
kthread+0x33f/0x460 kernel/kthread.c:259
usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #1
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #0
usb usb9: usbfs: interface 0 claimed by hub while 'syz-executor.2' sets config #1
usb 19-1: enqueue for inactive port 0
usb 19-1: enqueue for inactive port 0
vhci_hcd: vhci_device speed not set
BFS-fs: bfs_fill_super(): loop0 is unclean, continuing
BFS-fs: bfs_fill_super(): loop0 is unclean, continuing
audit: type=1800 audit(1642001627.375:533): pid=27512 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="file0" dev="sda1" ino=15423 res=0
audit: type=1804 audit(1642001627.385:534): pid=27512 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir973954080/syzkaller.wki1pA/294/file0" dev="sda1" ino=15423 res=1
audit: type=1800 audit(1642001627.655:535): pid=27525 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="file0" dev="sda1" ino=13895 res=0
audit: type=1804 audit(1642001627.685:536): pid=27525 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir973954080/syzkaller.wki1pA/295/file0" dev="sda1" ino=13895 res=1
BFS-fs: bfs_fill_super(): loop0 is unclean, continuing
audit: type=1804 audit(1642001627.685:537): pid=27525 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir973954080/syzkaller.wki1pA/295/file0" dev="sda1" ino=13895 res=1
audit: type=1800 audit(1642001627.805:538): pid=27589 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.3" name="file0" dev="sda1" ino=14067 res=0
audit: type=1804 audit(1642001627.805:539): pid=27589 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.3" name="/root/syzkaller-testdir973954080/syzkaller.wki1pA/296/file0" dev="sda1" ino=14067 res=1
base_sock_release(00000000ff1f6038) sk=00000000f8aa5d4d
UDF-fs: bad mount option "00000000000000000000g 18446744073709551615" or missing value
base_sock_release(00000000894756de) sk=000000002478218b
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 27671 Comm: syz-executor.0 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:sctp_ulpq_store_reasm net/sctp/ulpqueue.c:321 [inline]
RIP: 0010:sctp_ulpq_reasm net/sctp/ulpqueue.c:610 [inline]
RIP: 0010:sctp_ulpq_tail_data+0x416/0x1030 net/sctp/ulpqueue.c:116
Code: 03 42 80 3c 28 00 0f 85 3d 0a 00 00 48 8b 1b 49 39 de 74 71 e8 3b 55 f0 f9 48 8d 7b 44 48 89 f8 48 89 fe 48 c1 e8 03 83 e6 07 <42> 0f b6 14 28 48 8d 43 47 48 89 c1 48 c1 e9 03 42 0f b6 0c 29 40
RSP: 0018:ffff88804f8af2a8 EFLAGS: 00010202
RAX: 0000000000000008 RBX: 0000000000000000 RCX: ffffffff87723098
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000044
RBP: ffff88802002a028 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000005 R11: 00000000563e041d R12: ffff88803c4e5258
R13: dffffc0000000000 R14: ffff88803c4e5268 R15: 0000000000000000
FS: 00007ff6f5d3e700(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff8bd16e000 CR3: 0000000011eda000 CR4: 00000000003426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1462 [inline]
sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline]
sctp_do_sm+0xbd2/0x5110 net/sctp/sm_sideeffect.c:1170
sctp_assoc_bh_rcv+0x345/0x650 net/sctp/associola.c:1073
sctp_inq_push+0x1da/0x270 net/sctp/inqueue.c:95
sctp_backlog_rcv+0x1e9/0x11e0 net/sctp/input.c:356
sk_backlog_rcv include/net/sock.h:952 [inline]
__release_sock+0x134/0x3a0 net/core/sock.c:2362
release_sock+0x54/0x1b0 net/core/sock.c:2901
sctp_wait_for_connect+0x301/0x530 net/sctp/socket.c:8635
sctp_sendmsg_to_asoc+0x19ca/0x1ea0 net/sctp/socket.c:2003
sctp_sendmsg+0xe23/0x1580 net/sctp/socket.c:2149
inet_sendmsg+0x132/0x5a0 net/ipv4/af_inet.c:798
sock_sendmsg_nosec net/socket.c:651 [inline]
sock_sendmsg+0xc3/0x120 net/socket.c:661
__sys_sendto+0x21a/0x320 net/socket.c:1899
__do_sys_sendto net/socket.c:1911 [inline]
__se_sys_sendto net/socket.c:1907 [inline]
__x64_sys_sendto+0xdd/0x1b0 net/socket.c:1907
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7ff6f73c8eb9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff6f5d3e168 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007ff6f74dbf60 RCX: 00007ff6f73c8eb9
RDX: 000000000000a830 RSI: 0000000020847fff RDI: 0000000000000004
RBP: 00007ff6f742308d R08: 000000002005ffe4 R09: 000000000000001c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc0c95988f R14: 00007ff6f5d3e300 R15: 0000000000022000
Modules linked in:
BUG: Bad rss-counter state mm:00000000117e2995 idx:3 val:1
BUG: non-zero pgtables_bytes on freeing mm: 4096
kvm: vcpu 0: requested 128 ns lapic timer period limited to 200000 ns
---[ end trace 74094e7609f0037f ]---
RIP: 0010:sctp_ulpq_store_reasm net/sctp/ulpqueue.c:321 [inline]
RIP: 0010:sctp_ulpq_reasm net/sctp/ulpqueue.c:610 [inline]
RIP: 0010:sctp_ulpq_tail_data+0x416/0x1030 net/sctp/ulpqueue.c:116
Code: 03 42 80 3c 28 00 0f 85 3d 0a 00 00 48 8b 1b 49 39 de 74 71 e8 3b 55 f0 f9 48 8d 7b 44 48 89 f8 48 89 fe 48 c1 e8 03 83 e6 07 <42> 0f b6 14 28 48 8d 43 47 48 89 c1 48 c1 e9 03 42 0f b6 0c 29 40
UDF-fs: bad mount option "00000000000000000000g 18446744073709551615" or missing value
RSP: 0018:ffff88804f8af2a8 EFLAGS: 00010202
base_sock_release(000000009c42fb9b) sk=000000003b66671e
RAX: 0000000000000008 RBX: 0000000000000000 RCX: ffffffff87723098
----------------
Code disassembly (best guess):
0: 03 42 80 add -0x80(%rdx),%eax
3: 3c 28 cmp $0x28,%al
5: 00 0f add %cl,(%rdi)
7: 85 3d 0a 00 00 48 test %edi,0x4800000a(%rip) # 0x48000017
d: 8b 1b mov (%rbx),%ebx
f: 49 39 de cmp %rbx,%r14
12: 74 71 je 0x85
14: e8 3b 55 f0 f9 callq 0xf9f05554
19: 48 8d 7b 44 lea 0x44(%rbx),%rdi
1d: 48 89 f8 mov %rdi,%rax
20: 48 89 fe mov %rdi,%rsi
23: 48 c1 e8 03 shr $0x3,%rax
27: 83 e6 07 and $0x7,%esi
* 2a: 42 0f b6 14 28 movzbl (%rax,%r13,1),%edx <-- trapping instruction
2f: 48 8d 43 47 lea 0x47(%rbx),%rax
33: 48 89 c1 mov %rax,%rcx
36: 48 c1 e9 03 shr $0x3,%rcx
3a: 42 0f b6 0c 29 movzbl (%rcx,%r13,1),%ecx
3f: 40 rex


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.